Abstract 147: Cardiotoxic Neighbourhoods: Variable Incidence of Cardiac Arrest in a Large Urban Area
Introduction: Specific determinants of Out of Hospital Cardiac Arrest (OHCA) in the general population are poorly known. Whether OHCA occurs in a randomly distributed fashion, or within specific geographical neighbourhood “clusters” has not been evaluated.
Objectives: To assess the distribution of the domiciles of victims of OHCA in a large urban area.
Methods: We included 1323 adults aged 20+ years who were treated for OHCA in the City of Toronto, Canada, where all OHCAs are captured by a single Emergency Medical Service. All participants were enrolled in the Resuscitation Outcomes Consortium Epistry database between 2006 and 2009. Using the patient's postal code of their home address all OHCA patients were spatially mapped within one of 140 Toronto neighbourhoods. Neighbourhood OHCA rates were standardized by 20–49, 50–74 and 75+ age groups, which also corrected for differences in population density. Standardized Incidence Ratios (SIR) — the ratio of observed cases of OHCA patients from a given neighbourhood to the expected number from this same area — were mapped by quintiles to visually inspect clusters of high- and low-CA rates across neighbourhoods.
Results: The median SIR of OHCA was 2.9 times higher in highest-risk vs. lowest-risk neighbourhoods (Figure).
Conclusions: A patient's risk of OHCA may vary based on the neighbourhood in which they live, and the gradient of risk may at times be extreme across adjacent neighbourhoods.
- © 2010 by American Heart Association, Inc.